/**
 *  Licensed to the Apache Software Foundation (ASF) under one
 *  or more contributor license agreements.  See the NOTICE file
 *  distributed with this work for additional information
 *  regarding copyright ownership.  The ASF licenses this file
 *  to you under the Apache License, Version 2.0 (the
 *  "License"); you may not use this file except in compliance
 *  with the License.  You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing,
 *  software distributed under the License is distributed on an
 *  "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 *  KIND, either express or implied.  See the License for the
 *  specific language governing permissions and limitations
 *  under the License.
 */
package org.codehaus.groovy.control;

import org.codehaus.groovy.antlr.AntlrParserPluginFactory;

/**
 * A factory of parser plugin instances
 *
 * @version $Revision$
 */
public abstract class ParserPluginFactory {
    public static ParserPluginFactory newInstance(boolean useNewParser) {
        if (useNewParser) {
            Class type = null;
            String name = "org.codehaus.groovy.antlr.AntlrParserPluginFactory";
            try {
                type = Class.forName(name);
            }
            catch (ClassNotFoundException e) {
                try {
                    type = ParserPluginFactory.class.getClassLoader().loadClass(name);
                }
                catch (ClassNotFoundException e1) {
                    ClassLoader contextClassLoader = Thread.currentThread().getContextClassLoader();
                    if (contextClassLoader != null) {
                        try {
                            type = contextClassLoader.loadClass(name);
                        }
                        catch (ClassNotFoundException e2) {
                            // ignore
                        }
                    }
                }
            }

            if (type != null) {
                try {
                    return (ParserPluginFactory) type.newInstance();
                }
                catch (Exception e) {
                    throw new RuntimeException("Could not create AntlrParserPluginFactory: " + e, e);
                }
            }
            // can't find Antlr parser, so lets use the Classic one
        }
        return new AntlrParserPluginFactory();
    }

    public abstract ParserPlugin createParserPlugin();
}
